"Whonix is a project to build an operating system that will offer the maximum privacy and anonymity possible straight out of the box. Its creator, 'Adrelanos', says the aim is to make it as hard as possible for privacy-conscious users to make missteps when it comes to remaining anonymous. 'It also provides loads of documentation and possibilities for interested users to make it even more secure,' he says." We've already covered Whonix before.

"As far as I know, they don't share services in quite the same way. At least what I've read would suggest that. But I may well be wrong there."

I've worked a bit with linux containers/namespaces, and they are great, very elegant. I only wished there were better userspace tools to make arbitrary adhoc process containers in much the same way KVM could make adhoc VMs, which is exactly why I wrote my own. Containers are pretty easy to work with in code (though at the time I wanted to punch someone over the linux+distro interface breakages, hopefully that's settled now).